Effect of Cardiac Autonomic Balance During Sleep on Elite Cycling Performance Following Fatiguing Exercise
Presentation Type
Poster
Keywords
Elite Cycling, RMSSD, Recovery, Heart Rate Variability
Department
Sports Medicine
Major
Sports Medicine, B.A
Abstract
Heart-rate variability characterizes cardiac autonomic balance, and provides a useful index of training load exposure, and hence an estimate of cumulative physical fatigue. However, the interaction between HRV and performance is less understood.
Purpose: To determine the predictive value of the Root Mean Square of Successive Differences (RMSSD) and Low to High Frequency Ratio (LF/HF) on cycling 4km TT performance following high-intensity (HI) exercise.
Methods: Four elite cyclists (mountain bike (F), cyclocross (M), triathlon (M), BMX (M)) performed three successive days of 4x5 min HI cycling bouts at 260W (F), and 375 ± 21.8W (M) separated by 5-7 min of recovery between each bout. Following completion of the HI protocol, athletes rested for 30 min and then performed a 4km TT on a Cyclus 2 ergometer. HRV was recorded the evening before the TT’s between 22:00h and 23:59h using a HealthPatch (Vital Connect, Campbell CA), and areas under the curve were computed for RMSSD and LF/HF ratio. Linear regression was performed to determine the relationship between RMSSD, LF/HF ratio and TT time.
Results: 4x5 min HI exercise bouts were sustained in all athletes except BMX where workload was reduced by 14% from day 1 to day 2. Progressive fatigue was evidenced by RPE’s increasing from 1km to 4km by 12.5±3.6% (Day 1) to 20.6±4.5% (Day 3). Day 1 to Day 3 data is shown in the table below;
TT time
TT Power
RMSSD area
LF/HF area
Mountain bike
+2.8%
-9.8%
-25%
+46%
Cyclocross
+5.2%
-2.4%
-11%
-50%
Triathlon
-2.9%
+6.6%
+29%
-16%
BMX
-0.5%
+6.5%
-4%
+3%
RMSSD v. TT time R2 for day 1-3 respectively was, -0.39, -0.29, and -0.60 (p=0.03 for grouped days). LF/HF v. TT time R2 for day 1-3 respectively was, 0.09, 0.59, and 0.18 (p=0.06 for grouped days).
Conclusion: Early sleep cycle HRV data prior to HI fatiguing cycling explains partially TT cycling performance in elite athletes.
Faculty Mentor
Dr. Holden MacRae
Funding Source or Research Program
Not Identified
Effect of Cardiac Autonomic Balance During Sleep on Elite Cycling Performance Following Fatiguing Exercise
Heart-rate variability characterizes cardiac autonomic balance, and provides a useful index of training load exposure, and hence an estimate of cumulative physical fatigue. However, the interaction between HRV and performance is less understood.
Purpose: To determine the predictive value of the Root Mean Square of Successive Differences (RMSSD) and Low to High Frequency Ratio (LF/HF) on cycling 4km TT performance following high-intensity (HI) exercise.
Methods: Four elite cyclists (mountain bike (F), cyclocross (M), triathlon (M), BMX (M)) performed three successive days of 4x5 min HI cycling bouts at 260W (F), and 375 ± 21.8W (M) separated by 5-7 min of recovery between each bout. Following completion of the HI protocol, athletes rested for 30 min and then performed a 4km TT on a Cyclus 2 ergometer. HRV was recorded the evening before the TT’s between 22:00h and 23:59h using a HealthPatch (Vital Connect, Campbell CA), and areas under the curve were computed for RMSSD and LF/HF ratio. Linear regression was performed to determine the relationship between RMSSD, LF/HF ratio and TT time.
Results: 4x5 min HI exercise bouts were sustained in all athletes except BMX where workload was reduced by 14% from day 1 to day 2. Progressive fatigue was evidenced by RPE’s increasing from 1km to 4km by 12.5±3.6% (Day 1) to 20.6±4.5% (Day 3). Day 1 to Day 3 data is shown in the table below;
TT time
TT Power
RMSSD area
LF/HF area
Mountain bike
+2.8%
-9.8%
-25%
+46%
Cyclocross
+5.2%
-2.4%
-11%
-50%
Triathlon
-2.9%
+6.6%
+29%
-16%
BMX
-0.5%
+6.5%
-4%
+3%
RMSSD v. TT time R2 for day 1-3 respectively was, -0.39, -0.29, and -0.60 (p=0.03 for grouped days). LF/HF v. TT time R2 for day 1-3 respectively was, 0.09, 0.59, and 0.18 (p=0.06 for grouped days).
Conclusion: Early sleep cycle HRV data prior to HI fatiguing cycling explains partially TT cycling performance in elite athletes.